The second day of junior high school (biological invader, sunset illusion (19,20)) answers two texts simultaneously.

Read the text and tell me in what order this article was written.

This topic grasps the content of the article as a whole by understanding the order of explanation.

This is a logical exposition, which is explained in a logical order. Starting with the explanation of the concept of "biological invader", this paper introduces the harm that "biological invader" brings to human beings, its destructive effect on the ecological environment, the reasons for its formation, the different views of the scientific community on "biological invader" and the measures taken by various countries in the world at present.

Secondly, this paper uses the methods of enumerating figures, giving examples and making metaphors. Try to find out from the text and talk about their expressive effect.

The 1. number is actually a way to illustrate with facts. Digital facts can also stimulate readers' imagination. For example, "Since World War II, nine species of native birds in Guam 1 1 have been wiped out by brown snakes, and the number of the remaining two species of birds is decreasing day by day, which is in danger of extinction at any time." During the 60 years from the 1940s to the present, the number of birds in Guam has decreased from 1 1 to two, which shows the harm of "biological invaders" to the natural ecology. "So far, people have spent billions of dollars to clean and replace pipelines." "In the United States alone, the economic loss caused by' biological invaders' is as high as more than 200 billion dollars every year ..." The figures in these two sentences naturally remind people of the great harm that' biological invaders' have done to mankind.

2. Give examples to support the point of view and make it more convincing. For example, dandelion and fish and shrimp in a mountain stream with very limited breeding time and spatial span are taken as examples to prove the statement that "in the early stage of human civilization, land and navigation technologies were underdeveloped, and the ecological balance of nature was not greatly damaged"; The invasion of European spotted shellfish, Asian longhorned beetle and South American red ant to North America is listed, which strongly illustrates the great harm that "biological invaders" have brought to mankind. Take the example of palm tree snake almost killing birds in Guam to illustrate the destruction of natural ecology by "biological invaders", and take the examples of fresh fruits and vegetables and transnational pets to illustrate the man-made reasons for the formation of "biological invaders"; A bill passed by the US House of Representatives to strengthen the inter-departmental monitoring of vehicles that may carry alien species shows that all countries in the world have taken corresponding measures to deal with "biological intruders".

3. Metaphor is to explain more vividly. For example, the concept of "biological invaders" is metaphorical in itself, which tells readers that the "immigration" behavior of such "invaders" will cause harm to human beings and nature; Comparing the European bamboos that landed in North America to "stowaways", they landed on the North American continent unconsciously and quietly caused harm to human beings; It is very vivid to compare the spread and trade route of pests around the world to "hitchhiking in transnational trade"

3. Do you know any other "biological invaders"? Have you ever found biological invasion in your life? If yes, tell the students.

This topic inspires students to apply what they have learned in real life and improve their awareness of preventing "biological intruders". The following is the latest report on "biological intruders". This report tells us: ① Today, "biological invaders" may still invade at any time; ② China has taken strict precautions against "biological invaders".